What do the rings of life mean?

What is the metaphor of life as an annual ring?

The years are passing by, and we are growing.

What does the annual ring mean?

1.① The annual periodic annular rims formed on scales, otoliths, gill cover bones and vertebrae in the growth process of fish, and the dense and alternating concentric rings on the surfaces of fish scales, gill cover bones and otoliths. Can infer the age of fish and so on.

The scale ring in fish refers to the dividing line between the narrow band formed in autumn and winter of that year and the wide band formed in spring and summer of the following year.

② concentric rings on the cross-section of woody plant stems. Each ring is an annual ring, including early wood with light and loose color grown in spring and late wood with deep and dense color grown in late summer and early autumn. Trees and shrubs common in temperate zones. Tropical trees grow all year round, and the annual rings are not obvious. Trees are living archives, and the annual rings in the trunk are records. It not only shows the age of the trees themselves, but also shows the annual precipitation and temperature changes. Tree rings may also record forest fires, early frost and chemicals absorbed from the surrounding environment.

2. How are the tree rings formed? First of all, we should talk about the structure and activity law of vascular cambium. 2. Vascular cambium (or cambium) is a secondary meristem with infinite meristem developed from procambium. In the life of a plant, it constantly produces secondary phloem outward and secondary xylem inward. 3. The cambium is composed of spindle primitive cells and ray primitive cells. Axially elongated spindle-shaped primitive cells, both ends of which are wedge-shaped, are mostly rectangular in cross section, and the tangential width is wider than the radial width, and the length of the cells is several times larger than the width. 4. Axial system of secondary xylem and secondary phloem is derived from spindle-shaped primitive cells. X-ray primitive cells are small in size, almost equal in diameter or slightly longer. This kind of primitive cells derive the radial system of secondary xylem and phloem.

3. Application of annual rings

Through annual rings, people can not only date many things, but also know the earthquakes, volcanic eruptions and climate changes that happened in the past, and also infer the future. The data of the International Program of Tree-ring Meteorology Relations will be extended to the year 17, which is much earlier than the industrial revolution when coal and oil were burned. Lamasher said: "Without this data base, if atmospheric scientists want to know the warming trend exactly, it will probably take 1 to 2 years to observe the temperature and carbon dioxide. By then, I am afraid it will be too late. "

What do you mean by annual rings?

They are circles on the cross section of trees. Because one year is longer, it is called annual rings.

What's the significance of annual rings?

it represents the number of secondary xylem formed in a year. In a tree, the number of annual rings gradually decreases from the base of the trunk upward.

Sometimes there may be two or more growth ring in a growing season, that is, two wheels or multiple wheels. For example, the cambium in the stem of Citrus has three activity peaks every year, so it can produce three annual rings. Some plants will also have multi-year rings because of the sudden change of climate, such as cold or hot, long-term drought or insect pests, and the attack of strong typhoon. Some people call the last round of several growth ring in a year the real annual ring, and the other rounds are collectively referred to as false annual rings or false annual rings. In some growing seasons, if frost is encountered, especially in the late stage, it is easy to damage the cambium primitive cells, resulting in irregular parenchyma bands, which are called trauma rings or frost rings. Some trees, due to the abnormal climate, make the cambium undifferentiated, and start to move again until the growth environment is suitable, forming annual rings, so that there will be a corresponding phenomenon of missing growth ring on the cross section of wood. For example, trees at the edge of semi-arid forests or wood at the base of some old trees often lack growth ring.

Woody plants growing in tropical or subtropical areas, such as eucalyptus, have no obvious four seasons in a year, and the cambium activity is almost non-stop all year round, so it is difficult to see the dividing line of growth ring or tree rings in wood. However, the wood of some tree species can be used to identify the boundary of growth ring by means of microscopic chemistry.

In the same growing season, the primary cells of cambium not only produce a large number of secondary xylem molecules inward, but also divide and differentiate outward into secondary phloem molecules, and these molecules also follow a certain arrangement pattern. Especially in the secondary phloem near the cambium area, according to the secondary phloem of phloem parenchyma or thick-walled tissue, the growth ring boundary of this part is blurred due to the expansion of some cells, or the extrusion deformation of some cells, and the formation of periderm. Growth ring or annual rings in the secondary phloem or bark parts outside cambium.

during the formation of wood rings, many internal and external factors have great influence on them. For example, in the porous wood tree species of dicotyledonous plants, there are no endogenous hormones in the cambium primitive cells of the whole plant before the bud germinates, and auxin is produced only after the bud germinates, and then the cambium begins to move on the lower side of the germination. As auxin moves downward, the activity of cambium gradually expands to the base of stem. Generally, the cambium at the base of the stem just wakes up when the leaves grow to half the size of maturity, but in the annual branches, new xylem molecules have already differentiated, and some even have lignified cell wall stalks. From the top of the trunk to the base, the interval between cambium activities can sometimes reach 8-1 weeks. On the contrary, in the ring-hole material, the cambium begins to move at almost the same time in all parts of the whole plant, so it can be speculated that the precursor of auxin may have already spread all over the cambium primitive cells, and once the bud expands, the precursor of auxin will be transformed into auxin that promotes the division of the cambium primitive cells. In most tree species, the differentiation time of new xylem molecules is from the third day to the eighteenth day after the leaves are unfolded. In addition, endogenous hormones such as gibberellin and cytokinin in plants are closely related to the division and differentiation of cambium primitive cells, the thickening of xylem molecular cell walls, and the transition from early wood to late wood.

can you explain how the rings are formed? What does the annual ring mean to our life?

Concentric rings on the cross section of woody plants' stems. Usually, it forms a ring every year, hence the name annual ring < P > In summer, when there is enough rain and nutrients, trees grow fast, the wood is looser and the color of wood is lighter; This is called early wood.

In winter, when there is not enough rain and nutrients, the trees grow slowly, the wood is denser and the color of the wood is darker. It's called late wood.

In addition, the south of a tree grows faster than the north, so the rings in the south are wider than those in the north.

each round represents the secondary xylem formed within one year, including early wood and late wood of that year.

Meaning: 1. In production and scientific research, the age of trees can be inferred according to the number of annual rings at the base of trunk.

2. It is inferred that under special circumstances such as insect pests and abnormal climate, false annual rings are formed in the stems of trees.

3. The tree rings also recorded natural phenomena such as volcanic eruptions and earthquakes. (For example, when Mount St. hellens erupts, a lot of dust and gas enter the stratosphere, blocking a large area of sunlight. This will make the temperature drop below freezing point, leaving a special mark called frost wheel in the tree. However, the earthquake will do harm to trees, and make them produce thinner annual rings in the next few years.)

4. The law of rapid growth of trees can be summarized from it to guide forestry production.

5. We can know the historical and long-term climate changes in a place from the changes of tree rings.

Basic meaning of annual rings

Formation of annual rings: When environmental conditions such as temperature and moisture are good (spring and summer), plants grow faster, and the xylem formed is sparse and light in color; When the environmental conditions such as temperature and moisture are bad (autumn and winter), the xylem formed is dense and dark. An annual ring includes spring wood and autumn wood of that year. Tree rings not only reflect the growth of plants, but also reflect whether the environmental conditions at that time are conducive to the growth of plants. The radial thickening of roots or stems of woody plants is mainly the result of pericentric division of spindle-shaped primitive cells, which is slow. For example, in conifers, it takes 4-16 days for each division (only 8-18 hours for meristem cells at the top of the stem). When a spindle-shaped primitive cell is divided into two daughter cells, one of them is derived from xylem mother cell (or xylem primitive cell) or phloem mother cell (or phloem primitive cell). The other still maintains the spindle-like primordial cell meristem state. During the active period of the cambium, some cells have divided or are dividing, and some are still in meristem state, so the cambium has become a fairly wide and undifferentiated cell area. In this region, there is a layer of true cambium primitive cells, including undifferentiated derived cells. Because it is difficult to distinguish the above-mentioned cells from their cell morphology, for convenience, people collectively refer to these cells as cambium zone (or cambium zone)! From the tangential section of cambium, the arrangement of cambium primitive cells can be roughly divided into two types: First, in the cambium of Tilia and Robinia, spindle primitive cells are arranged in almost the same horizontal layer, which is called superimposed cambium. One is the invasion and growth of spindle-shaped primitive cells, which make the ends of longitudinally elongated cells staggered and not arranged on the same horizontal layer, so it is called non-overlapping cambium, such as Castanea and Juglans. In order to adapt to the radial thickening of stems or roots, spindle-shaped primitive cells also divide themselves to increase the number of primitive cells, which is called proliferation and division. In different plants, the ways of proliferation and division are different. For example, in plants with overlapping cambium, radial vertical division is the main way, while in conifers and some dicotyledonous plants with non-overlapping cambium, it is usually false horizontal division, or oblique vertical division. It is a common phenomenon that ray primitive cells are formed from spindle primitive cells by division. The ray primitive cells themselves also divide horizontally or vertically, and finally form single or multi-column rays. Woody plants growing in temperate regions are also obviously reflected in the periodic activities of cambium with seasonal climate changes. In winter, the cambium primitive cells stopped differentiating, and then resumed their activities in the following spring, and gradually weakened in summer and autumn, and then stopped their activities. This goes on and on, year after year. When the cambium primitive cells resume their activities, they can be divided into two stages: (1) The cambium primitive cells extend radially and the radial wall becomes very thin, which makes them vulnerable to frost. (2) Primitive cells begin to divide, which is often one to several weeks later than the previous stage. For tree species growing in Beijing, the cambium begins to move in the first and middle days of April every year. In most tree species, when the cambium begins to differentiate, phloem molecules often differentiate one month or more before xylem, or both of them differentiate almost at the same time. The time when cambium differentiation stops varies greatly in different habitats and tree species, and the trees growing in the north temperate zone are mostly concentrated in September. In spring, when the cambium resumes its activity, the spindle-shaped primitive cells rapidly divide inward and differentiate into a large number of xylem molecules. At this time, the differentiated tracheid or vessel molecules are larger in diameter, more in number, thinner in wall and less in wood fiber, so the material appears loose, and this part of wood is called early wood (or called spring wood). In the summer and autumn of the same year, the activity of cambium gradually weakened, and the speed of pericentric division of primitive cells slowed down accordingly. The diameter of differentiated cells was small and the number was small, while the number of wood fibers increased accordingly. This part of the material was relatively dense, called late wood (or summer wood). In the annular wood of dicotyledonous plants (such as oak and ash), the diameter of vessel molecules in early wood is obviously increased, while that in late wood is quite small. In porous wood and gymnosperm wood, the change from early wood to late wood is generally gradual, that is, there is no obvious boundary. However, there is a clear boundary between the late wood in the last growing season and the early wood in the next growing season. Seen from the wood cross-section of roots and stems, these boundaries form concentric circles, and each circle including early wood and late wood is called growth ring (or growth layer). Woody plants growing in temperate regions usually form only one growth ring within one year ... >; >

what do tree rings mean?

The annual rings are the age of trees, which is caused by the change of seasons. In summer, trees grow fast, so the density of trunks is small, the color is light, while in winter, the density of trunks is high, and the color is deep, forming rings.

What are the secrets in life, for example, tree rings

You are still there except the secrets in stone books, me.

I used to live in such a quiet life. What does it mean to chew the seasons and rings in vain?

I used to live like this and live in obscurity, recalling the years and the helplessness of life in the illusion year after year.